Cooking apparatus.



R. M. G. PHILLIPS.

COOKING APPARATUS.

APPLICATION FILED APR.6, 1914.

1, 1 1 0,079, Patented Sept. 8, 1914.

3 SHEETS-SHBET 1.

R. M. G. PHILLIPS. COOKING APPARATUS. APPLICATION 11,111) Ares, 1914.

Patented Sept. 8, 1914.

3 SHEETS-SHEET 2. e i

R. M. G. PHILLIPS.

COOKING APPARATUS. APPLIOATION FILED APR. 6, 191.4.

Patented Sept. 8, 1914.

3 EHEETB-SEEET 3.

@ZTM I UNITED STATES PATENT OFFICE.

ROSS M. G. PHILLIPS, OF WEST HAVEN, CONNECTICUT, ASS IGNOR TO THE AUTOMATIC STOVE CO., OF MINNEAPOLIS, MINNESOTA, A CORPORATION.

COOKING APPARATUS.

Specification of Letters IPatent.

Patented Sept. 8, 1914.

Application filed April 6, 1914. Serial No. 829,996.

To all whom it may concern Be it known that 1, Ross M. G. PHILLIPS, a citizen of the United States, residing at West Haven, in the county of New Haven and State of Connecticut, have invented a new and useful Improvement in Cooking Apparatus; and I do hereby declare the following, when taken in connection with the accompanying drawings and the characters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this application, and represent, in-

Figure 1 a view in front elevation of a cooking apparatus embodying my invention, with the food-container in its lowered or heat-conserving position in which its ingross and egress draft-passages are closed and sealed. Fig. 2 a view thereof in side elevation with the cover of the food-container shown in its open and suspended position by broken lines. Fig. 3 a plan view of the apparatus with the cover of its foodcontainer in place. Fig. 4 a view of the apparatus in vertical central section on the line (1-1; of Fig. 3, looking toward the gas supply lvalve and the means employed for automatically controlling and operating the same, the food-container being shown in its elevated heat-charging position in which its ingress and egress draft-passages are open. Fig. 5 a view of the apparatus in rear elevation with the'food-container removed and the entire rear wall of the casing broken away. Fig. 6 a view corresponding to Fig.

4: but showing the food-container in its lowered or heat-conserving position with its lower end broken away to show the utilization of the weight of the container to prevent the untimely turning on of the gas. Fig. 7 a view of the appa'ratus'in transverse section on the line c(Z of Fig. 4, showing the pro-heater by broken lines. Fig. 8 a broken detail view in horizontal section on the l ne e-f of Fig. 5, showing the latch in its relation to the suspension-member of the lifting-rod.

My invention relates to an improvement in that class of cooking apparatus in which the food-container is automatically released at a predetermined time and.permitted to descend from its heat-charging into its heatconserving position in which its fuel-supply is cut off and in which its ingress and egress draft-passages are closed and sealed, the ob-' ject being to produce a simple, convenient, reliable and efiicient apparatus of the character described, constructed with particular reference to o eration in a predetermined sequence, where y accidents and waste of fuel are avoided, as well as the burning or overcooking of the food due to failure to set the automatic controlling mechanism the setting of which is a condition precedent to the subsequent operations.

Vith these ends in view, my invention consists in a cooking apparatus having certain details of construction and combination of parts as will be hereinafter described and pointed out in the claims.

In carrying out my invention as herein shown, I employ a vertically movable cylindrical food-container 2 having concentric inner and outer walls 3, 4, separated by an annular space filled with asbestos 5 or equivalent non-conducting material. A radiator 6 of soapstone or metal of any approved form, and either fixed or removable, is by preference located within the lower end of the food-container 2 in position to be heated or charged during the relatively short period during which the apparatus has an actual fire in it. At its lower end the said container 2 is formed with a relatively large ingress draft-passage 7 which is open when the container is in its suspended spaced or heatcharging position and which is closed and sealed when the container is in its lowered or heat-conserving position at which time the cooking is mainly done.

At its upper end the container 2 is provided with a double-walled insulating cover 8 packed with non-conducting material 9 and formed with a concentric egress draftpassage 10 smaller in diameter than the ingress draft-passage 7 aforesaid, and provided at its upper end with a flanged, annular valve-seat 11 receiving a disk-valve 12 having an asbestos sealing-pad 13 applied to its lower face and furnished with a valvemounted sofas to have rocking movement in stem 14 encircled by a valve-spring 15 and a sleeve lfi glooated in the forward end of a substanti'aily horizontal valve carrying lever 17 hung by a pin 18 in a bracket 19 mounted upon the top of the cover 8 toward the 'rear edge thereof. The said valve 12 is normally supported above the valve-seat 11 by means of a spring 2Q;interposed 'between the lever 17 and the top-0f the cover 8. At

shown in Fig. 6.

Lilomtt its rear end the said lever 17 is furnished with an operatingarm 21 which extends into a vertical loop 22 formed in the upper end of a vertically-adjustable wire, valveoperating frame 23 extending above the food-container 2 when the same is in its elevated position and having its legs or ends secured within the casing 24 at the back thereof by means of a clamping-bar 25 and bolts 26. By providing for the vertical adjustment of the frame 23, the same may be accurately set for automatically forcing the valve 12 upon the seat ll when the foodcontainer descends from its heat-charging position which it is shown in Fig. 4, into its heat-conservin position in which it is he spring 20 provides for opening the valve automaticall and maintaining it open, except when t e container descends into its lowered or heat-charging position.

As shown in Fig. 1, the upper end of the frame 23 is contracted to permit either of the handles 91 of the cover 8 to he slipped over it, for the purpose of suspending the cover when the food container is being filled gr emptied as shown by broken lines in As shown, the casing 24 in which the food-container2 is mounted, is rectangular in form, though its particular shape is im- .material. As shown, it is supported upon legs 27. lit is formed in its fiat top 28 with a circular opening 29 just enough larger in ,diameter than the diameter of the food-container 2 to ermit the same to be set down into the casing above which it always projects whether in its elevated or lowered position, the amount of its vertical movement being small. For the purpose of holding the container 2 in spaced relation to the preheater 66 to be described later on, I suspend it in the said casing 24 upon two opposltely located horizontal suspension arms 30 (Fig. 5) respectively bent inward at a right angle from the lower ends of two vertically arranged sliding spacing or suspension-bars 31 having their main portions set inwardly to form .vertical guides 32 which assist in keeping the food-container 2 centered with respect to the opening. 29 in the casing 24. The said bars 31 are furnished at their upper and lower ends with slots 33 receiving guidepins34 extending inward from the opposite side walls of the casing 24. The said spacing or suspension-bars 31 are lifted for lifting the container 2 by means of a lever-system comprising a horizontally arranged yoke 35 (Figs. 4, 5, 6 and 7)- extending forwardly in the casing 24', and having its respective arms pivoted by pins 36 to the lower ends of the said bars 31, and formed with slots 37 receiving studs 38 upon which the-yoke itself swings. The. forward portion of the yoke is pivotally' connected at its center with the lower end of the lifting-rod or shank 39 of a handle 40 extending upward through a perforation in the flat top 28 of the casing 24, as clearly shown in Figs. 3 and 4. The said rod 39 carries a spacing-member 41 forming at its lower end a spacingshoulder 42 and at its upper end a stop shoulder 43. As shown in Fig. 5, I employ a yielding centering-bar 44 and a rigid centering-bar 93 respectively located within the front and back walls of the casing 24 to coact with the guides 32 of the bars 31 in centering the food-container 2 as it moves up and down. 4

The food-container 2 is latched, as it were, in its spaced relation to the preheater 66, or, in other words, in its suspended, heatcharging position, (Figs. 4 and 5), by means of a bell-crank latch 45 hung within the front of the casing 27 upon a stud 46 and having its lower end adapted to be inserted under the spacing-shoulder 42 at the lower end of the spacing-member 41. The horizontal upper arm of the said latch 45 terminates at its outer end in a depending lug 47 which rests upon a tripping-lever 48 hung by its inner end upon a stud 49 in the front of the casing 24 and entered at its opposite end into the automatic controlling or timing-mechanism 50 which may be of any approved construction, such as that shown 1n my co-pending application filed August 13, 1913, Serial No. 782,445.

A spring 51 connected with the lever 48 exerts a constant efi'ort to lift it and so. swing the latch 45 on its stud 46 for the release of the lifting-rod 39, and hence of the suspension-yoke 35, whereby the food-container is released or fired, and allowed to descend by gravity into its heat-conserving position'in which it rests upon the preheater 66, as will be more fully described later on.

As shown in Fig. 1, the automatic control,- ling-mechanism 50 is furnished with a graduated-dial 52 located on the outside of the front of the casing 24 and with a settinglever 53 mounted on the main-arbor 54, having at its upper end an index-finger 55 sweeping over the said dial and provided at-its lower end with a handle 56. At its inner end the arbor 54 carries (Fig. 5), a timing-disk 57 having a timing-slot 58 adapted to receive a timing-pin 59 mounted 48 and permit it to be lifted by the spring 51 to swing the latch 45 on its stud 46 for releasing the lifting-shank 39 and hence the food-container-2.

To forestall, as it were, or anticipate the action of the automatic controlling-mechanism 50, as may sometimes be desired for one reason-or another, I mount a forestallin'g pin 62 (Fig. 4) in'the lower arm of the latch 45 and extend 'the same forward through a slot 63 in the front of the casing 24. By manually moving the projecting forward end of this pin 56, the latch 45 may be swung at any time so as to release or fire the food-container 2 and permit the descent of the same into its sealed, heatconserving position.

The spacing-mechanisms of the fireless cookers of my co-pending applications Serial No. 710,630, filed July 20, 1912, and Serial N0.-737,993 filed December 21, 1912, are manually set for the suspension of the food-container by the lateral movement of the lifting-handle and the engagement of a shoulder upon it with the outside of the casing. In my present application the spacing-mechanism is located entirely within the casing with the single exception of the han dle 'which'is confined to vertical movement and has no lateral-movement, the place of which is taken by the latch 45 and spring 51, both of which are located entirely within the casing, whereby the fireless cooker of my present application is improved in appearance and its liability to derangement minimized since the spacing-mechanism is not exposed in such a way as to permit it to he accidentally tripped by the catching of the handle, or to be tampered with. l

The descent of the food-container 2 is stopped by its being brought to rest upon a horizontally arranged sealing-pad or plate 64 of asbestos or equivalent material superimposed upon and overhanging the flange 65 of the pre-heater or burner-body 66, the said pad 64 being enough larger than the ingress draft-passage 7 1n the bottom of the food-container 2 to completely close the same when the bottom of the container is brought to a bearing upon the pad, whereby the passage 7 is not only closed, but the container 2 also virtually sealed and insulated. When, on the other hand, the food-container is inits elevated, spaced or heat-charging position, its bottom is separated by a horizontal draft-space 67 from the said pad 64 and hence from a circular burner 68 (Fig. 7) superimposed upon the pad and provided with a circular series of burner-nipples 69 grouped in a circle-enough smaller than the diameter of the passage 7 to permit the nipples to be inclosed by and within the passage when the descent of the food-container into its heat-conserving position closes or eliminates the draft-space 67.

The burner-body 66 forming the preheater proper, is carried b the sheet-metal drawer or tray 70 located etween guides 71 (Fig. 5) securedto the bottom of the casing 24. The said tray is moved back and forth through an opening 72 formed in the lower portion of the'front of the casing and closed when'the drawer is in its closed position, by means of the flange 7 3 rising from the front end thereof. The said flange 73 is formed with a door 74 having a handle 75 enabling the user'to note the operation of the burner at any time. The tray is also furnished with a handle 90 applied to the said flange 73.

'My improved cooking apparatus is not limited to the use of gas as a fuel. It is, however, so constructed as shown herein. For this purpose the forward end of the burner-body '66 is provided with a gascoupling 76 (Fig. 4) having a needle-valve 77, and providing for the attachment of one end of a flexible gas-pipe 78" coiled within the tray 7 0 and having its opposite end connected to a fixed valve-body 79 mounted in the forward end of a gas-pipe 80 located within the right hand lower corner of the casing 24 and connected at its rear end with a nipple 81 projecting laterally through the right hand wall of the casing for the attachment of a gas-supply pipe not shown.

The valve-body 29 contains a valve not in itself shown,'but provided with a projecting valve-stem 82 furnished with an operatingarm 83 pivotally connected with the inner end of an operating rod 84 (Fig. 6) projecting forward through the front of the casing 24 and furnished with a knob-handle 85 which, when drawn forward into the position shown in Fig. 4, turns the valve-stem 82 so as to turn on the gas.

To prevent the gas from being prematurely turned on, or at any other time than when the food-container 2 is in its proper elevated or heat-charging position, I provide the valve-stem 82 with another operating-arm '86 standing at an angle of 45 to the arm 83 aforesaid and pivotally connected with-the lower end of a gas-supply guardrod 87 formed with a horizontal guardshoulder 88 and passing loosely upward through a perforation in a lug 89 located upon the right hand arm of the yoke 35 as shown in Figs. 4 and 6, from which it results that when the food-container 2 is in 'its lowered or heat-conserving position, the

lug 89 engages with the shoulder 88 in such a way as to prevent the rod'87 from being lifted which in turn prevents the rod 84 from being pulled forward by the knob 85 for turning on the gas. When, however,

, the food-container 2 is properly lifted, this obstruction to the outward movement of the rod 84 is removed.v Conversely, when the foo'd container 2 descends, the downward pressure of the lug 82 upon the shoulder 88 pushes the rod 87 downward from the .position shown in Fig. d into the position shown in Fig. 7 whereby the descent ot the food-container from its heat-charging into its heat-conserving position automatically effects the cutting oil of the gas after which the weight of the food-container itself prevents the gas from being turned .on until the container has been properly raised by means of its handle 40 which must be precoded by thesetting oi the timing-mechanlsm.

In the operation of my improved cooln'ng apparatus, the food, whatever it character may be, is placed in suitable receptacles within the food-container 2, after which the cover 8 is placed thereupon in the usual manner. The subsequent steps now to be taken, follow each other in a predetermined succession desi nod to preclude mistakes and to secure sa ety. In the first place, the auto matic controlling mechanism 50 is set by drawing the handle (Fig. 1) downward from left to right, whereby the pin 59 is withdrawn from the slot 58 in the dish'57 (Fig. 5) after which the said dish is turned by the setting-lever 53 until its index-finger 55 has been brought to the desired mark upon the graduated dial 52, leaving the pin 59 in engagement with the periphery of the disk 57, whereby the tension of the spring 51 is removed from the latch 45 now left free to have its lower arm swung by the weight of its upper arm into its latching position. The food-container 2 is now manually raised by lifting upward on the handle d0 until the shoulder 42 of the uspension-member 45 has been lifted above the lower end of the latch 45 sutficiently to permit the lower end of the lower arm of the same to swing under it, whereby the food-container is latched in its suspended or elevated or spaced position. The raising of the food-container 2 as'described, releases the tray which may now be pulled outward by its handle 90 into its lighting position in which the burner 68 is substantially cleared from the casing 27.

The food-container 2 having been lifted, the

gas-supply guard-rod 87 is relieved of downward pressure, permitting the handle 85 to be utilized in turning on the gas, which is now lighted with the nipples 85 in the open air where there is no danger of explosion which might occur it the burner was lighted within the casing with an accumulation of gases within" the same. The tray 70 is now tit pushed inward into its closed position, the inward and outward movement of the tray being ermitted by the flexibility oi" the pipe 78. W en the food-container 2 was raised into its elevated position, the spring 29 was brought into lay for automatically lift ng the valve 12 om its seat it, thus opening the egress draft-passage it) in the cover 8.

11,1l more The container now being suspended in its elevated or heat-charging position, and its ingress openin 7 and egress opening 10 bemg open and t e burner 68 being lighted, a draft of air will flow into the draft-space 67 in which it will be heated and rise through the assage 7, and after circulating through tinues for the predetermined time to which the time-mechanism 50 was set. At the expiration of thi time, the slot 58 in the disk 67 will register with the in 59 and allow the spring 51 to assert. itse f to lift the tripping-lever 48 against the nose d7 of the latch 45 which will swun on its stud 47 and its lower end retracte from beneath the shoulder 42, whereby the food-container is automatically tripped or fired and allowed to descend until it is stopped by the bringing of its bottom to a bearing directly upon the asbestos sealing and insulatingad 64, whereby the ingress draft-passage is closed and sealed. At the same time the egress draft-opening 10 in the cover 8 is automatically closed and sealed by the ressure of the arm 21 upon the bottom 0 the loop'22 of the upstanding frame 23, thereby overcoming the tension of the spring 20. The ingress draft-passage 7 and the egress draft-passage 10 having thus been closed, the radiator 6, if used, and the food-container 2 will retain their accummulated heat over a considerable length of time determined by the amount of heat initially charged into them and the rapidity of the radiation of such heat from them. The descent oi the food-container 2 automatically shuts 0d the gas at the valve-body 79 and also locks the tray 70 in its closed position, whereby the gas cannot be again turned on after the extinguishment of the burner 68 until the food-container 2 has again been raised and suspended in its elevated position which must be preceded by the setting of the timing-mechanism 50, and so on. If at any time it is desired to fire the foodcontainer before the time at which the timing-mechanism 50 was set, has expired, it is only necessary to manually operate the forestalling-pin 62 which takes the place of the timing-mechanism, in swinging the latch 45 out of en agement with the suspensionsmember n of the lilting than to.

lit will thus be seen that the parts of my improved cooking apparatus, are constructed and organized so thatthe same must be operated in a predetermined sequence which ill eliminates mistakes proceeding-from forgetfulness on the part of the housewife, and also secures safety. Thus it prevents the food-container from being suspended until after the automatic controlling mechanism has been set, otherwise, there being no timelimit set. the heating would go on indefinitely, wasting gas and destroying the food if any food had previously been placed in the container.

Again my improved construction prevents the gas from being carelessly or ignorantly turned on by pulling out the knob 85, until after the automatic controlling mechanism has been set and the food-container has been suspended in its elevated position. These two steps being conditions precedent to the turning on of the gas, danger in that respect is negligible.

In a broad view of my invention, the preheater may be moved toward and away from the food-container as shown in my co-pending application filed February 12, 1914, Serial No. 818,279, instead of vice versa as herein shown and described.

I claim 1. In a cooking apparatus, the combination with a casing, of a food-container and a preheater one of which parts is movable with respect to the other, spacing-mechanism located within the casing for holding the said movable part in spaced relation to the other part, automatic mechanism co-acting within the casing with the said spacing-mechanism for controlling the releasing function thereof the said spacing and automatic mechanisms being constructed and organized to make the setting of the automatic mechanism a condition precedent to the holding action of the spacing mechanism, and means for manually forestalling the action of the automatic-mechanism in releasing the said spacing-mechanism.

2. In a cooking apparatus, the combination with a casing, of a vertically movable food-container, a preheater, spacing-mechanism located within the casing for holding the said container in spaced relation above the said preheater, automatic mechanism co acting within the casing with the said spacing-mechanism for controlling the releasing function thereof the said spacing and automatic mechanisms being constructed and organized to make the setting of the automatic mechanism a condition precedent to the holding action of the spacing mechanism, and means for manually forestalling the action of the timing-mechanism in releasing the container.

3. In a cooking apparatus, the combination with a food-container and a preheater, one of the said parts being movable with respect to the other, spacing mechanism lo-' cated within the casing for holding the said movable part in spaced relation to the other part, the said spacing mechanism including a latch, automatic mechanism co-acting with the said latch, for controlling the releasing function of the said spacing-mechanism the said spacing and automatic mechanisms being constructed and organized to make the setting of the automatic mechanism a condition precedent to the holding action of the spacing mechanism, and means projecting through the said casing and co-acting with the said latch for manually forcstalling the action of the automatic controlling mechanism in releasing the said movable part.

4. In a cooking apparatus, the combination with a casing, of a vertically movable food-container, a preheater, spacing-mechanism for holding the food-container above the preheater-in spaced relation thereto including a latch, automatic mechanism controlling the releasing function of the spacing-mechanism, and a pin mounted in the said latch and projecting through the casing for forestalling the action of the said automatic mechanism in releasing the container.

5. In a cooking apparatus, the combination with a food-container, of a preheater, one of the said parts being movable with respect to the other, spacing-mechanism for holding the' niovable part in spaced relation to the other part, and automatic mechanism controlling the releasing function of the spacing-mechanism, the said spacing and automatic mechanisms being constructed to make the setting of the automatic mechanism a condition precedent to the holding action of the spacing-mechanism.

6. In a cooking apparatus, the combination with a casing, of a vertically movable food-container, a preheater, spacing-mechanism for holding the. food-container n spaced relation above the preheater, the said spacing-mechanism discharging its holding and releasing function at a protected po nt within the casing, and an automatic mechanism controlling the releasing function of the spacing-mechanism, the i said spacing and automatic mechanisms being constructed to making the setting of the automatic mechanism a condition precedent to the suspension of the vertically movable container. 115

7. In a cooking apparatus, the combination with a casing, of a vertically movable dli food-container, a preheater, spacing mechanim for holding the container in spaced relation to the preheater, automatic mechanism controlling the releasing function of the said spacing-mechanism the holding action whereof is dependent upon the prior setting of the said automatic mechanism, and fuel-supplying means controlled in shutting oh the fuel from the preheater by the descent of the container and in turning on the fuel by the lifting of the container.

10. In a cooking apparatus, the combination with a casing, of a vertically movable food-container, a laterally movable pre-r heater located below the same, spacing mechanism for holding the food-container in spaced relation above the preheater, automatic mechanism controlling the releasing function of the spacing-mechanism in releasing the container which descends upon the preheater, the said spacing and automatic mechanisms being constructed and organized to make the setting of the automatic mechanism a condition precedent to the holding action of the spacing mechanism, and means for laterally moving the preheater into its lighting and heating ositions when released by the lifting o the container.

11. In a cooking apparatus, the combination with a vertically movable food-container, of a preheater, spacing-mechanism for holding the said container in spaced relation above the preheater, automatic mechanim controlling the releasing function of the spacing-mechanism the holding action of which is conditional upon the prior setting of the said automatic mechanism, a valve for supplying fuel to the preheater, manually operable means for opening the said valve, and guarding means operated by the said spacing-mechanism to automatically close the valve when the container descends and to blodk the manual opening of the valve until thecontainer is raised.

12., 'lln a cooking up aratus, the combination with a casing, of a vertically movable food-container, a laterally movable. preheater, spacing-mechanism' for holding the container in spaced relation above the preheater, automatic mechanism controlling the releasin function of the said spacing-mechanism w ich is constructed to melts the set ting of the said automatic mechanism precede the suspension of the said container, means controlled by the said spacing-mechanism for operating the said valve, and means for laterally moving the said preheater into its lighting position outside of the said casing and back under the container when the same is in its raised position.

13. In a cooking apparatus, the combination with a casing, of a food-container having an ingress draft-passage in its lower end and an egress draft-passage in its upper end, of a preheater adapted to act as a closure for the said ingress draft-passagegupon the descent of the container, spacing-mechanism for holding the container in spaced relation to the preheater, automatic mechanism controlling the releasing function of the said spacing-mechanism which will not function to suspend the container until after the automatic mechanism has been set, a normally open valve for the said egress draft-passage, and means for automatically closing the said valve upon the descent of the container.

14. ln a cooking apparatus, the combination with a casing, of a vertically movable food-container, vertically movable spacingbars located within the casing for supporting the container, a yoke for operating the spacing-bars, a handle connected with the yoke for manually lifting the container, automatic mechanism controlling the release of the handle and the descent of the container the said spacing and automatic mechanisms being constructed and organized to make the setting of the automatic mechanism a condition precedent to the holding action of the spacing mechanism, a preheater, and a fuelsupplying' mechanism connected with the yoke and controlled thereby forshutting oil the supply of fuel from the preheater upon the descent of the container. i

15. In a cooking apparatus, the combination with a casing, of a vertically movable food-container, a laterally movable preheater, spacing-mechanism for holding the container in spaced relation-above the preheater, automatic mechanism controlling the releasing function of the said spacingmechanism which is constructed to function for the suspension of the containeronly after the automatic mechanism has been set, a gas-valve located within the casing, a flexi- Ill ble pipe connecting the said valve with the preheater, and means connecting the said gas-valve with the said spacing-mechanism for the control of the gas-supply by the same.

l8, lit a cooking apparatus, the combination with a casing, of a vertically movable food-container havin an ingress draft-passage in ,its lower on and an egress draftpassage in its cover, of a laterally movable preheatcr adapted to act as a closure for the said ingress draft-passage, spacing-mechanism for holding the container in spaced relation above the preheater, automatic mechanism for controlling the releasing function of the spacing-mechanism the suspension function of which necessitates the prior setting of the automatic mechanism, a normally open valve for closing the said egress passage, means for operating the said Valve to automatically close the said egress passage, means for laterally moving the preheater into its exposed and inclosed posi- 

